How Apple's Anti-Snooping Technology Can Protect iPhone Users' Privacy

Let's imagine for a second that you have done some things that you shouldn't have done. The police would very much like to have a word with you, and they're interested in who you speak to over the phone as well as what sort of communication you exchange. You, on the other hand, are not that keen. What can you do to keep law enforcement officers away?

Well, in 2017, Apple filed a patent that might just solve some of your problems. Although it's some two years old now, the patent didn't really catch the attention of regular users until The Telegraph wrote about it last week. Before we take a look at what type of technology we're talking about, however, we need to understand how police officers track and eavesdrop on suspects.

IMSI catchers

As you probably know, your mobile phone works because of the cell towers you often see on top of buildings. What you may not know is that in order to get the reception, your phone must first authenticate itself which happens via your IMSI or International Mobile Subscriber Identity – a unique 64-bit string that your mobile device sends to the cell tower.

Capturing a suspect's IMSI is high on law enforcement's priority list. It's a unique identifier which means that the police can determine a person's location by seeing which cell towers receive their IMSI. This is where the so-called IMSI catchers come in.

As the name suggests, an IMSI catcher captures the IMSIs of the phones around it by impersonating a cell tower. Because they relay the connection between the devices and the real cell tower, the person operating an IMSI catcher can be considered a Man in the Middle.

IMSI catchers can also force mobile phones in the area to use a weak encryption protocol or no encryption at all meaning that phone calls can be recorded and eavesdropped on with relative ease.

Apple to use end-to-end encryption to combat IMSI catchers

The use of IMSI catchers is rather loosely regulated in most countries, and law enforcement and intelligence agencies the world over aren't too happy to share statistics on how often they employ this particular technique to track down suspects. We know that IMSI catchers are around us, though, and even if you've done nothing wrong, you shouldn't discount the possibility of your phone being hooked up to one at any given time.

Police officers can't capture just one IMSI or record the phone calls from just one phone. They indiscriminately snoop on every single device within the IMSI catcher's range. Many consider this a massive invasion of privacy, and Apple seems to agree.

According to the 2017 patent, the technology giant has found a way of end-to-end encrypting the communication between mobile phones and cell towers. Modern communication protocols also use encryption of some kind, but as we mentioned already, if the IMSI catcher's operator is sophisticated enough, they can force the mobile devices to switch to older, weaker protocols.

With Apple's solution, this shouldn't be possible, and because we're talking about end-to-end encryption, unscrambling the information requires two keys and is therefore a lot harder. What are we waiting for, then?

Well, commercializing a new piece of technology is a long, complicated process, and filing a patent is a very small portion of it. There are still plenty of unknowns like, for example, whether the tech requires new cell tower hardware and whether Apple plans to let other manufacturers use the protocol and protect non-iPhone users' privacy.

Killing this particular means of tracking and snooping on people's phone calls will have both positive and negative consequences. It's fair to say, however, that for the time being, IMSI catchers are here to stay. Keep that in mind and try not to fall in the police's sights.